1. Technical Field
The present invention relates generally to devices for the protection of construction workers at the work site, and more particularly to a temporary rooftop and stairway safety rail system for installation at the edge of a either a flat or pitched roof or on an unprotected stairway to prevent workers from falls.
2. Background Art
Roofing or other rooftop construction work performed at some height, and work on unprotected stairways, are inherently dangerous undertakings, the obvious danger being the risk of falling. Any job-related injury suffered by a worker results in lost company productivity and profitability, and governmental losses related to paying out for workman's compensation claims. So great is the risk of falling, and so frequent are injuries resulting from rooftop and stairway falls, that the United States Occupational Safety and Hazard Administration (OSHA) now requires a rooftop barrier to be placed at the edge of a roof where work is being performed. OSHA standards require that the barrier be placed approximately 42 inches above the roof edge and be able to withstand a 200 pound static load in multiple directions.
Several solutions to the problem of rooftop safety have been proposed, some comprising elaborate, expensive, and unwieldy ground-based scaffolding systems, other consisting of little more than simple roping systems that involve securing or anchoring workers to the roof with ropes connected to a wearable harness. The latter systems, dubbed “tie-off” systems, have obvious disadvantages, including the difficulty in finding suitable anchors and the awkwardness of working in a harness among a network of ropes. A few relatively recent solutions directed to rooftop safety rail systems include the following:
(1) U.S. Pat. No. 5,515,941 to Palmer et al, which discloses a guard structure for installation at the edge of a building roof eave to assist in shingling. The system employs a plurality of spaced roof cleats nailed to the roof, each having a hinge at its lower end with a hinge axis parallel to the eave. Each hinge connects the cleat to a respective vertical support member at a junction portion immediately adjacent to the eave. The portion of the support member below the eave or roof line engages the building structure, e.g. the rafter tail or fascia board, usually through a pressure plate, and may carry a screw-threaded adjustment member for adjusting the vertical attitude of the support member. The other portion of the support member has a lower outward upward inclined part carrying a toe board retainer member for an inclined toe board, and an upper vertical part carrying at least two vertically spaced back rail support members, as is usually required by safety regulations. The toe board and the back rails form a safety structure for the roofer. Metal safety straps may be provided extending longitudinally beneath the toe boards to prevent catastrophic breakage if they sag excessively. The upper vertical part may also be provided with a retainer for a vertical horizontally extending catch board; when such a catch board is provided it cooperates with the toe board to form a catch space to prevent debris falling from the structure to the ground and also provides an improved safety structure.
While the roof eave mounting guard structures disclosed in Palmer et al provides some measure of protection from falling from a rooftop, in order to be attached to a rooftop it requires that a fascia board be fastened to the outer ends of the roof's rafter frames. Furthermore, it extends outwardly from the end of the roof, thereby having limited structural strength and integrity.
(2) U.S. Pat. No. 5,647,451, to Reichel, teaches a portable roof guard rail support device adapted for fastening directly to a pitched roof. It may be adjusted to the pitch of the roof. The system comprises a roof attachment plate for attaching directly to the roof, a support beam pivotally connected to the roof attachment plate, an angle adjustment brace removably connected to the roof attachment plate and rotatably connected to the support beam for varying the angle at which the support beam is connected to the roof attachment plate, a plurality of cross bar channels through the support beam for attaching removable cross bars, and a channel within the support beam for storing the angle adjustment brace for transportation.
The roof guard rail support device of Reichel attaches directly to the pitched rooftop itself; thus, it is not well suited for work in removing or installing new roofs. Additionally, the Reichel device must be positioned inwardly at least some distance from the edge of the roof as its base plate, which supports the support beam, extends down the slope of the roof from the lower end of the support beam. Accordingly, at least some area of the roof is inaccessible while the roof guard rail support device is installed.
(3) Finally, U.S. Pat. No. 5,711,398 to Bartholomew, discloses a safety rail system for use during construction or maintenance repair of pitched roofs. The system includes multiple, spaced apart rail support assemblies, each of which resides over a respective joist and provides means for receiving and supporting safety planks. Each support assembly is detachably secured in place by a J-hook structure that is inserted into the gap between adjacent courses of roof sheet overlay and lockingly engages the underlying joist.
The patent to Bartholomew teaches another rooftop safety rail system that must be attached directly to the pitched roof. Accordingly, it has the same disadvantages as those in Reichel. Additionally, it does not permit installation on a vertical wall rather than a pitched roof, and this limitation applies to each of the other above-described devices. Thus, it is not suited for installation on an elevated walkway, stairway, or wall adjacent a flat roof.
It would therefore be desirable to provide a temporary rooftop and stairway safety rail system that allows for rapid and easy deployment, installation, and removal, and is adapted for installation on either a wall or the spaced-apart parallel rafters of a pitched roof. In providing such a system, the present invention represents a substantial improvement over the foregoing and other prior art safety rail systems.